Stable, single phase w/o microemulsion matrix formulation for forming sprayable, aerosol agriculturally active compositions

ABSTRACT

Stable, single phase w/o aerosol microemulsion final use compositions containing a sprayable agriculturally active composition are described herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to microemulsion compositions, and, moreparticularly, to stable, single phase w/o microemulsion matrixformulations for forming sprayable aerosol agriculturally activecompositions.

2. Description of the Prior Art

Microemulsion compositions are known in the art for deliveringagriculturally active ingredients to a desired site. Such compositionsusually are pump sprayed onto the target location. However, for a morerapid, 100% knockdown (kill) rate for insecticides it is desired toprovide an aerosol system of a water-based formulation whichaccommodates a maximized quantity of water in an w/o microemulsionmatrix.

SUMMARY AND DETAILED DESCRIPTION OF THE INVENTION

In accordance with the invention, a water-based, w/o microemulsionmatrix, is provided herein which can accommodate an agriculturallyactive ingredient and an aerosol propellant as stable, single phasesystems for delivery of spray particles of the active ingredient to aninsect-infected site. These compositions are effective in producing a100% kill at a substantially instantaneous knockdown rate. Themicroemulsion formulations can accommodate large amounts of water andthe agriculturally active ingredient (insecticides), and a desirableamount of propellant loading, all within a stable, single phasemicroemulsion having predetermined amounts of oil, emulsifier andcosolvent/cosurfactant components.

The liquid microemulsion matrix of the invention (without agriculturallyactive ingredient and propellant) can be formulated as desired with aparticular active ingredient for final use, e.g. an insecticide, such asD-allethrin, D-phenethrin, and the like; a herbicide, a fungicide, orany useful agricultural chemical.

In particular, the stable, sprayable w/o single phase microemulsion ofthe invention can deliver aerosol particles of about ≦0.05 micronscontaining an insecticide which is capable of 100% kill (knockdown) oftarget insects within 5 minutes.

The matrix formulations and final use compositions of the invention aredescribed below.

                  TABLE 1                                                         ______________________________________                                                           Weight %                                                   Component            Suitable Preferred                                       ______________________________________                                        (a) Oil                   2-20     5-10                                           long chain (C.sub.8 -C.sub.18)                                                hydrocarbon                                                                   e.g. dodecane                                                             (b) Water                20-50    25-30                                       (c) Propellant           20-45    25-40                                           e.g. C.sub.3 -C.sub.4 mixed                                                   hydrocarbon, A-46                                                         (d) Emulsifier           10-25    12-20                                           e.g. nonylphenyl                                                              ethoxylate with 5-12 EOs,                                                     preferably 6-10 EOs ahd,                                                      most preferably, 9-10 EOs,                                                    such as Igepal ® CO-520,                                                  CO-630, CO-660 and CO-730                                                 (e) Cosolvent/Coemulsifier                                                                             15-35    20-30                                           e.g. long chain (C.sub.8 -C.sub.18)                                           alkyl pyrrolidone, preferably                                                 octylpyrrolidone (Agsol ® Ex 8);                                          and/or pentanol                                                           (f) Agriculturally Active                                                                              0.01-5   0.05-2                                          Ingredient                                                                    e.g. insecticide,                                                             such as D-allethrin or                                                        D-phenethrin                                                              ______________________________________                                    

A matrix composition not containing the propellant is described below.

                  TABLE 2                                                         ______________________________________                                                           Weight %                                                   Component            Suitable Preferred                                       ______________________________________                                        (a)    Oil                3-25     5-15                                       (b)    Water             25-45    30-40                                       (d)    Emulsifier        13-25    15-22                                       (e)    Cosolvent/Coemulsifier                                                                          18-40    20-30                                       ______________________________________                                    

A matrix composition not containing the propellant, however, with anagriculturally active ingredient is shown in Table 3.

                  TABLE 3                                                         ______________________________________                                        Formulation of Table 2                                                                           Suitable Preferred                                         ______________________________________                                        (f)   Agriculturally Active                                                                          0.015-6  0.06-2.5                                            Ingredient                                                              ______________________________________                                    

A matrix composition with propellant is described below in Table 4.

                  TABLE 4                                                         ______________________________________                                                           Weight %                                                   Component            Suitable Preferred                                       ______________________________________                                        (a)    Oil                2-20     5-10                                       (b)    Water             25-50    25-30                                       (c)    Propellant        20-45    25-40                                       (d)    Emulsifier        10-25    12-20                                       (e)    Cosolvent/Coemulsifier                                                                          15-35    20-30                                       ______________________________________                                    

These single phase, water-based microemulsion matrix and usecompositions can be stored at 5° C. as a single phase system, and at 45°C., without phase separation. Furthermore, even after centrifugation at3000 rpm for 30 minutes, there is no evidence of phase separation of themicroemulsion.

If desired, UV-protecting monomers, oligomers and oils can be loadedinto the matrix and final use compositions to provide UV protection forthose agriculturally active ingredients which are sensitive to sunlight.

EXAMPLES

                  TABLE 5                                                         ______________________________________                                                   EXAMPLE NO.                                                        Ingredients  1        2     3      4   5                                      ______________________________________                                        Dodecane     10       12    14      6  15                                     Igepal ® CO-520                                                                        --       --    --     --  18                                     Igepal ® CO-630                                                                        20       --    --     --  --                                     Igepal ® CO-660                                                                        --       11    21     27  --                                     Igepal ® CO-730                                                                        --        9    --     --  --                                     Gafac ® RE-610                                                                         --       --    --     --   2                                     Agsol ® Ex-8                                                                           36       13     8      0  15                                     Pentanol     --       20    11     27  11                                     Glycerol     --       --    10     --  --                                     Water        34       35    36     40  50                                     ______________________________________                                    

                  TABLE 6                                                         ______________________________________                                        RESULTS                                                                               EXAMPLE NO.                                                                   1      2      3         4     5                                       ______________________________________                                        Appearance                                                                              clear    clear  clear   clear clear                                 at RT                                                                         Appearance                                                                              clear    clear  cloudy  clear cloudy                                at 40-45° C.                                                           Propellant                                                                              ≧35%                                                                            35%    >25%    ≦25%                                                                         25%                                   loading                                                                       capacity                                                                      Appearance                                                                              clear    clear  clear   clear clear                                 after propellant                                                              loading at room                                                               temperature                                                                   Appearance                                                                              clear    clear  clear   clear --                                    at 45° C. with                                                         propellant                                                                    ______________________________________                                    

What is claimed is:
 1. A stable single phase w/o aerosol microemulsionmatrix for making a sprayable agriculturally active composition,consisting essentially of, by weight,(a) 2-20% of a C₈ -C₁₈ hydrocarbon,(b) 25-50% of water, (c) 20-45% of a propellant, (d) 10-20% of anemulsifier, and (e) 15-35% of a cosolvent/coemulsifier which is a C₈-C₁₈ alkyl pyrrolidone or pentanol, or mixtures thereof.
 2. A matrixaccording to claim 1 wherein (a) is 5-10%, (b) is 30-40%, (c) is 25-40%,(d) is 12-18%, and (e) is 30-40%.
 3. A matrix according to claim 1wherein (a) is a C₁₂ hydrocarbon, and (d) is a nonylphenyl ethoxylatewith 5-12 EOs.
 4. A matrix according to claim 1 wherein (c) is a C₃ -C₄mixed hydrocarbon.
 5. A matrix according to claim 1 wherein (d) is anonylphenyl ethoxylate with 6-10 EOs.
 6. A matrix according to claim 1wherein (a) is 10% dodecane, (b) is 34%, (c) is 30%, (d) is 20% and (e)is 35%.
 7. A stable single phase w/o aerosol microemulsion compositioncomprising the matrix formulation of claim 1 and (f) 0.01-5% by weightof an agriculturally active ingredient.
 8. A composition according toclaim 7 wherein (f) is an insecticide.
 9. A composition according toclaim 7 including 0.05-2% of (f).
 10. A composition according to claim 7wherein (f) is a pyrethroid.
 11. A composition according to claim 7wherein (f) is D-allethrin or D-phenethrin, or mixtures thereof.
 12. Astable, single phase w/o microemulsion matrix for making a sprayableagriculturally active composition, consisting essentially of, byweight,(a) 3-25% of a C₈ -C₁₈ hydrocarbon, (b) 25-45% of water, (d)13-25% of an emulsifier, (e) 18-40% of a cosolvent/coemulsifier which isa C₈ -C₁₈ alkyl pyrrolidone or pentanol, or mixtures thereof.
 13. Amatrix according to claim 12 wherein (a) is 10-15%, (b) is 30-35%, (d)is 15-22%, and (e) is 20-25%.
 14. A matrix according to claim 12 wherein(a) is a C₁₂ hydrocarbon, and (d) is a nonylphenyl ethoxylate with 5-10EOs.